Integration Drafts

[kahboom]

Add support for saving integrations and similar files as drafts in the browser session. "Similar files" can mean object model files for data mapping and transformations, but as a first step it should at least cover the main YAML file for the integration.

Epic #1693

Is your feature request related to a problem? Please describe. Yes. I often cannot finish designing an integration in a given moment, and need to come back to it later on, maybe even the next week. How can I save my work without starting over again?

Describe the solution you'd like I would like to persist my changes between sessions (using localStorage if need be), so that if I close the browser and reopen it the next day, my work will still be there.

Describe alternatives you've considered Saving the YAML (or data mapping XSLT) file to my computer and uploading it again later on. But it would be very inconvenient and not possible for other people to collaborate on it.

We also having the following issue open (https://github.com/KaotoIO/kaoto-ui/issues/1533), however, it's impractical to expect that people who want to quickly work with Kaoto will first go set up authentication with GitHub/Gitlab. They should be able to get started easily, close their browser, and still have the work there when they come back to it.

Considerations

For data mapping (#253) we need to consider that mapping files can become quite large, so we should consider to have some mechanism in place to prevent users from saving massive files in localStorage. However, for quick and relatively small mappings and transformations, this is an ideal way to enhance the user experience.

Relates to #609

[kahboom]

Related to https://github.com/KaotoIO/kaoto-ui/issues/1533